Railway traffic controlling apparatus



Sept. 22, 1931.

B. E. o HAGAN 1,824,619

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Oct. 20, 1930 Fig.2.

lNl-"EN'I'OR. B E 077 77 7 7 Patented Sept. 22, 1931 UNITED STATES 1 PATENT OFF-ICE BERNARD OHAG-AN, OF SWISSVALE, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL CO1V[PANY, OF SWISSVAIJE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA RAILWAY TRAFFIC CONTROLLING APPARATUS Application filed October 20, 1930. Serial No. 489,780.

My invention relates to railway traffic controlling ;apparatus, and particularly to apparatus of the type involving train carried governing mechanism controlled by energy received from the trackway. More particularly, my present invention relates to the trackway portion of such apparatus, and has for an object the provision of novel means for controlling the application of coded train controlling current to the track rails of a main section of railway track when one rail of such section has been divided to form an auxiliary section in which a car might stand without shunting the train controlling current away from the rails of the main section in rear of the auxiliary section.

I will describe two forms of apparatus embodying my invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a diagrammatic viewillustrating one form of apparatus embodying my invention. Fig. 2 is a similar view showing a modified form of the apparatus illustrated in Fig. 1, and also embodying my invention.

Similar reference characters refer to similar parts in both views.

Referring first to Fig. 1, the reference characters 1 and 1 designate the track rails of a stretch of railway track over whichtraificnormally moves in the direction indicated by the arrow. These track rails are divided by means of insulated joints 2, to form a plurality of main track sections, of which only two, AB and B-C, are illustrated in the drawings. Each main tracksectionris provided with a track circuit comprising a source of current, designated by the reference character T with a distinguishing exponent, and a main track relay, designated by the reference character R with a distinguishing exponent. As here shown, the source of current T for each main track section is a track transformer, the secondary 3 of which is connected across the rails of thesection ad.- jacent the exit end of the section inseries with the usual current limiting impedance 4. The primary 6 of transformer T is constantly supplied with alternating current from the terminals X and Y of a suitable source of minals X andY in a manner which will be described hereinafter. The track relay R for each section comprises two windings 7 and 8, the former of which, 7, is connected across the rails of the section adjacent the entrance 7 end of the section, and the latter of which, 8, is constantly supplied with alternating current from the terminals X and Y.

The lower rail 1 of section A.B is divided, by means of insulated joints 2, to form an auxiliary track section 9, and the track circuit current for the main section A B is carried around the auxiliary section 9 by a conductor 1-0. The auxiliary section9 is provided with a track circuit comprising atransformer T and an auxiliary track relay R".

An auxiliary track section located within a main track section,and provided with a track circuitin the manner just described, is particularly suitable for, although in no way limited to, use in systems for controlling hi-gh way crossing signals, such for example, as the system disclosed and claimed in the pending application for Letters Patent of the United States Serial No. 468,538, filed by George W.

Baughman, on July 17, 1930, for apparatus for the control of highway crossing signals. The means for controlling the highway cross ing signals by the auxiliary track section forms no part of my present invention, and is therefore omitted from the drawings for the sake of simplicity. When an auxiliary track section of the type described is located within a main track section, however, and it is desired to supply the rails of the main track section with train controlling current which cooperates with train carried governing apparatus to control the movement of trains through the section, it is necessary to insure that no train controlling current will be supplied to the rails of the main section in the event that a single car is inadvertently left standing in the auxiliary section, because such a carwould not shunt the train controlling current away from the rails of the main section in rear of the auxiliary section, and a dangerous condition might result. For this purpose, I provide the apparatus which I will now proceed to describe.

This apparatus, as here shown, comprises a coding relay D, a checking relay F, a coder control relay E, and a slow releasing repeater relay G. The coding relay D, in the form here shown, comprises a winding 11, and two contacts 12 and 13 which are periodically operated at different frequencies when the relay is energized. For example, for purposes of illustration, I will assume that when coding relay D is energized, contact 12 is periodically operated at a frequency of 180 times per minute whilecontact 13 is periodically operated at a frequency of times per minute.

Relay G is controlled by a front contact 23 of track relay R and it will be apparent, therefore, that this relay is energized or de energized according as track relay R is energized or deenergized.

Relay E is provided with a pick-up circuit which passes from terminal X through back contact 14 of track relay R front contact 15 of track relay R and the winding of relay E to terminal Y. Relay E is also provided with a stick circuit which passes from terminal X through back contact 14 of track relay R front contact 16 of relay E, and the winding of relay E to terminal'Y.

Relay F is provided with a pick-up circuit which passes from terminal X through front contact 17 of track relay R front contact 18 of track relay'R, back contact 19 of relay E, and the winding of relay F to terminal Y. Relay F is also provided With two stick circuits, one of which passes from terminal X through front contact 20 of track relay R front contact 21 of relay F, and the winding of relay F to terminal Y, andthe other of which passes from terminal X through back contact 22 of relay Gr, front contact 21 of relay F, and the winding of relay F to terminal Y.

Coding relay D'is provided with a pickup circuit which passes from terminal X through, front point of contact 25 of relay F, front contact 24 of relay E, and winding 11 of re lay D to terminal Y.

The primary 6 of transformer T is provided with one circuit which passes from terminal X through back contact 26 of relay E and primary 6 to terminal Y, and withanother'circuit which passes from terminal X through back point of contact 25 of relay F and primary 6 to terminal. Y. lVhen either of these circuits isclosed, the rails of section AB are supplied with uninterrupted track circuit current, and track relay R is energized. The primary 6 of transformer T is also provided with a circuit which passes from terminal X through front point of contact 25 of relay F, front contact 24 of relay E, contact 12 of relay D, front point of contact 27 of track relay R and primary 6 to terminal Y. When this circuit is closed, the rails of section AB are supplied with alternating train controlling current which is periodically interrupted at a frequency of 180 times per minute, this current hereinafter being designated as high speed code. The primary 6 of transformer T B is further provided with a circuit which passes from terminal X through front point of contact 25 of relay F, front contact 24 of relay E, contact 13 of relay D, back point of contact 27 of track relay R and primary 6 to terminal Y. 'W hen this circuit is closed the rails of section AB are sup plied with alternating train controlling current which is periodically interrupted at 80 times per minute. This latter current I shall hereinafter designate as low speed code.

It should be pointed out that, while for purposes of illustrating my invention, I have shown means for periodically varying the train controlling current at only two rates, my invention is not limited to this number.

The train controlling current supplied to the rails of section AB is intended for co operation with train carried governing means forming no part of my invention, and is therefore not illustrated in the drawings. For purposes of the present disclosure, it is sufficient to say that, when high speed code is being supplied to the rails of section AB, a train traversing the section will receive a proceed indication on board the train; when low speed code is being supplied to the rails of section A-B, a train traversing the section will receive a caution indication; and when no code is being supplied to the rails of the section, a train traversing the section will receive a slow indication.

As shown in the drawings, section A-B, the auxiliary section 9, and section BC, are all unoccupied. The track relays R R and R are therefore all energized. Both the pick-up and stick circuits for relay E are therefore open at back contact 14 of track relay R and relay E is therefore deenergized. The pick-up circuit for relay F is closed so that this relay is energized, and relay G is also energized. Relay D, however, is deenergized, the circuit for this relay being open at frontcontact 24 of relay E.

In explaining the operation of the apparatus as a whole, I will first assume that with the parts in the conditions just described, a train enters section A-B. Track relay R will therefore become deenergized, and will open its front contact 17 and close its back contact 14, The opening of front contact 17 of track relay R will interrupt the pick-up circuit for relay F, but as long as track relay B is energized, the stick circuit for relay F including front contact 20 of track relay R will still be closed, and relay F will therefore remain energized. The closing of back contact 14 oftrack relay R will complete the pickup circuit for relay E, and relay E will therefore become energized, and will complete its stick circuit at its front contact 16. It will be apparent, therefore, that relay E will now remain energized over its stick circuit, even though track relay R becomes deenergized due to the train entering the auxiliary section 9. When relay E becomes energized, the supply of uninterrupted track circuit current to the rails of section AB will be cut off due to the openingof back contact 26 of relay E, and since relay F is still energized, coding relay D will become. energized. High speed code will then be supplied to the rails of section AB, and as a result, the train will receive a proceed indication which permits it to proceed at full speed through the section. When the train enters section B-C, track relay R will become deenergized, and will open its front contacts and 23. The opening of front contact 20 of track relay R will interrupt the stick circuit which was previously closed for relay F at this contact, and the o ening of front' contact 23 of track relay will open the circuit for relay G. Due to the fact that relay G is slow releasing, a considerable interval of time will elapse after its circuit is opened, before it will close its back contact 22 and, since the stick circuit for relay F including contact 20 of track relay B is opened at the same time that the circuit for relay G is opened, by the time back contact 22 of relay G has become closed, relay F Will have become deenergized. It will be apparent, therefore, that under these conditions, the closing of back contact 22 of relay G will not complete the stick circuit for relay F including this contact. The deenergization of relay F will deenergize coding relay D, and will also interrupt the supply of train controlling current to the rails of section A--B. Furthermore, the deenergization of relay F will complete the circuit for primary 6 of transformer T including the back point of contact 25, so that after the train has passed completely out of section A-B, the rails of this section will be supplied with track circuit current which will pick up track relay R This, in turn, will deenergize relay E, thereby completing the circuit for primary 6 of transformer T including back contact 26 of relay E. If track relay R is then energized, as will be the case if no car has been left standing in auxiliary section 9, the deenergization of relay E will also complete the pick-up circuit for relay F, and relay F will pick up. When relay F picks up, it will interrupt the circuit for the primary 6 of transformer T which was previously closed at back point of contact of this relay, and it will also complete its stick circuit including back contact 22 of relay G. It follows that if a following train now enters section A-B, relay F will'remain energized. When the train has passed completely out' of section BC, track relay R will pick up and will complete the stick circuit for relay F including contact 20, as well as the circuitfor relay G. Relay G will therefore pick up, and the apparatus will then. be restored to the condition in which it is illustrated in the drawings. It will be noted that during the picking up of track relay R there is no interruption in the supply of current to relay F because the stick circuit for relay F including contact 20 of track relay R becomes closed before the stick circuit for relay F including back contact 22 of relay G becomes opened.

If a second train enters section A.B before the preceding train has left the section, the second train will not receive train controlling current even after the first train has passed completely out of this section. For, as soon as the first train enters section BO and deenergizes track relay R relay F will become deenergized in the manner previously described and when this first train passes completely out of section AB, relay R will remain deenergized due to the second train. As long as relay R is deenergized, the pick-up circuit for relay F willbe open at front contact 17 of track relay R and relay F cannot, therefore, be again energized to complete the circuit for coding relay D. The following train will therefore receive a slow indication throughout section AB under these conditions,

I will now assume that a following train enters section AB after a preceding train has passed completely out of this section but is still in section BC. Under these conditions, at the instant the following train enters the section AB, track relays R and R and relay F will all be energized, but relays E, G and D, and track relay R will all be deenergized. As a result, when relay R becomes shunted by the train, it will com plete the pick-up circuit for relay E in the manner previously described, and will interrupt the pick-up circuit for relay F." Relay F will not become deenergized under these conditions, however, because, since re-- lay G is now deenergized, the stick circuit for relay F including contact 22 of relay G will be closed. i/Vhen relays E and F are both energized,the circuit for coding relay D is completed, and relay D will become energized. Low speed code will then be supplied to the rails of section A-B over back point of contact 27 of track relay R and the train will therefore receivea caution indication as it proceeds through the section. lVhen the-following train has passed out of section AB, track relays R and R will both become energized. Relay E will thereforebecome deenergized, and will deenergize coding relay D. Vhen the following train has passed out of section B-C, (it being understood that the preceding train passed out of this section before or shortly after the following train entered the section) track relay R will pick up and will completethe circuit for relay G, so that this relay will also pick up. The apparatus will then be restored to the conditions in which it is illustrated in the drawings.

I will next assume that a first train leaves a car standing within the auxiliary section 9 which would not shunt current away from the rails of themain' section AB in rear of the auxiliary section, and that after the first train has passed completely out of section AB, a second train enters the section. As long as auxiliary section 9 is occupied by the car, track relay R will be deenergized, and since the pick-up circuit for relay F includes a front contact 18 of track relay R it follows that relay E, which became deenergized when the first train entered section BC, is prevented from again becoming energized as long as the car occupies the auxiliary section. 'When relay F is deencrgized, the circuit for coding relay D is open at front point of contact 25 of relay F, and no train controlling current can be supplied to the rails of section AB. As a result, when the following train enters section lei-13, under these conditions, a slow indication will be received on the train, and it will be appar-' ent, therefore, that a dangerous condition would not exist.

In the modification shown in Fig. 2, the use of relay F has been rendered unnecessary by providing relay E with two stick circuits which are controlled by relays R and G, respectively. The stick circuit for relay E which is controlled by relay R passes from terminal X through back contact 14 of track relay R front contact 20 of track relay R front contact 16 of relay E, and the winding of relay E to terminal Y. The

stick circuit for relay E which is controlled by relay G passes from terminal X through back contact 14 of track relay R back contact 22 of relay G, front contact 16 of relay E, and the winding of relay E to terminal Y. Relay D, as here shown, is controlled solely by a. front contact 24 of relay E. The remainder of the apparatus is substantially the same as that shown in Fig. 1.

In explaining the operation of the apparatus shown in Fig. 2, I will first assume that with the parts in the conditions in which they are illustrated in the drawings, a train enters section AB. This deenergizes track relay R and since relay R is energized, the pickup circuit for relay E then becomes closed. Relay E therefore becomes energized, and completes its stick circuit including front contact 20 of track relay R so that relay E will now remain energized as long as front contact 20 of track relay R remains closed. l/Vhen relay E is energized, the supply of track circuit current to the primary 6 of transformer T is interrupted at back contact 26 of relay E, and the circuit for relay D is completed at front contact 24: of relay E. Relay D therefore becomes energized, and since relay B is now energized, high speed code is supplied to section AB. The train may therefore proceed at full speed through the section. When the train enters section B C, the shunting of track relay R deenergizes relay G and also interrupts the stick circuit which was previously closed for relay E at front contact 20 of track relay R WVhen the stick circuit for relay E is interrupted, relay E becomes deenergized, with the result that relay E cannot again become energized unless track relay R is picked up, thereby insuring that train controlling current will not be supplied to section AB and a following train, if a car should be left standing in section 9 by the first train. Furthermore, when relay E becomes deenergized, the circuit for primary 6 of transformer T including back contact 26 of relay E is completed, so thatwhen the train has passed completely out of section A-B, track circuit current is supplied to track relay R and this relay picks up. lVhen the train passes out of section BC, track relay R again becomes energized and energizes relay G. The parts are then restored to the positions in which they are illustrated in the drawings.

1 will now assume that after a first train has passed completely out of section AB, but is still in section BC, a following train enters section AB. \Vhen track relay R becomes shunted by the following train, relay E will become energized as previously described, and will complete the circuit for coding relay D. Coding relay D will therefore become energized, and since track relay B is now deenergized, low speed code will be supplied to the rails of section AB. The energization of relay E, under these conditions, will also complete its stick circuit in cluding back contact 22 of relay G. As a result, if the preceding train now leaves section BC, relay E will remain energized because when track relay R picks up, its front contact 20 will become closed and will complete the other stick circuit for relay E before relay G becomes energized and interrupts the stick circuit for relay E including back con tact 22 of relay G. With relay E energized and track relay R picked up, the rails of section AB in advance of the following train will be supplied with high speed code, and the following train may proceed through the remainder of section AB at full speed. lVhen the following train passes out of sec tion AB, the coded current supplied to the rails will pick up track relay R which will interrupt the stick circuit for relay E and hence deenergize relay E. When the following train has passed completely out of section BC, track relay R and, hence, re-

lay G, will again become energized. The parts will then be restored to the condition in which they are illustrated in the drawings.

It should bepointed out that the supply of current to the primary 6 of transformer T may be periodically varied in well known manner to produce coded train controlling current for influencing the train carried apparatus of a train occupying section BC. Means for producing this result have no bearing upon the present disclosure and are not shown in the drawings.

Although I have herein shown and described only two forms of railway trafiic controlling apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a first main section of railway track, one of the rails of which is divided to form an auxiliary section, a track circuit for said main section including a main track relay, a track circuit for said auxiliary section including an auxiliary track relay, a third relay controlled by said two track relays, and means controlled by said third relay for supplying train controlling current to the rails of said main section.

2. In combination, a first main section of railway track, one of the rails of which is divided to form an auxiliary section, a track circuit for said main section including a main track relay, a track circuit for said auxiliary section including an auxiliary track relay, a third relay controlled by a back contact of said main track relay and a front contact of said auxiliary track relay, and means controlled by said third relay for supplying train controlling current to the rails of said main section.

3. In combination, a first main section of railway track, one of the rails of which is divided. to form an auxiliary section, a track circuit for said main section including a main track relay, a track circuit for said auxiliary .section including an auxiliary track relay, a third relay, a pick-up circuit for said third relay including a back contact of said main track relay and a front contact of said auxiliary track relay, a stick circuit for said third relay including said back contact of said main track relay and a front contact of said third relay, and means controlled by said third relay for supplying train controlling current to the rails of said main section.

l-. In combination, a first main section of railway track, one of the rails of which is divided to form an auxiliary section, a sec- W ond main section of railway track adjacent the exit end of said first main sectlon, a track section controlled by said fourth relay and by said second main track relay.

5. In combination, a first main SOCtlOH'Of railway track, one of the rails of which is divided to form an auxiliary section, a second main section of railway track adjacent said first main section, a track circuit for said first main section including a first main track relay, a track circuit for said auxiliary section including an auxiliary track relay, a

track circuit for said second main section ineluding a second main track relay, and means controlled by said three track relays for supplying train controlling current to the rails of said first main section. v

6. In combination, a first main section of railway track, one of the rails of which is divided to form an auxiliary section, a second main section of railway track adjacent said first main section, a track circuit for said first main section including a first main track relay, a track circuit for said auxiliary section including an auxiliary track relay, a track circuit for said second main section including a second main track relay, a fourth relay controlled by said three track relays, and means controlled by said fourth relay and by said second main track relay for supplying train controlling current to the rails of said first main section.

7. In combination, a first main section of railway track one of the rails of which is divided to form an auxiliary section, a sec ond main section of railway track adjacent the exit end of said first main section, a track circuit for said first main section including. a first main track-relay, a track circuit for said second main section including a second main track relay, a track circuit for said auxiliary section including an auxiliary track relay, slow-releasing relay controlled by said second main track relay, and means controlled by all of said relays for supplylng train controlling current to the rails of said first main section.

8. In combination. a first main section of railway track, one of the rails of which is divided to form an auxiliary section, a second main section of railway track adjacent the exit end of said'first main section, a track circuit for said first mainsection including a first main track relay, a track circuit for said second main section including a second main track relay, a track circuit for said auxiliary including an auxiliary track relay,

a slow releasing relay controlled .by said second main track relay; a fifth relay controlled by said slow releasing relay, said first main track relay and said auxiliary track relay; and means controlled by said fifth relay for supplying train controlling current to the rails of said first main section.

9. In combination, a first main section of railway track, one of the rails of which is divided to form an auxiliary section, a second main section of railway track adjacent the exit end of said first main section, a track circuit for said first main section including a first main track relay, a track circuit for said second main section including a second main track relay, a track circuit for said auxiliary section including an auxiliary track relay, a slow releasing relay controlled by said second main track relay; a fifth relay controlled by said slow releasing relay, said first main track relay and said auxiliary track relay; and means controlled by said fifth relay, and by said second main track relay for supplying train controlling current to the rails of said first main section.

10. In combination, a first main section of railway track, oneof the rails of which is divided to form an auxiliary section, a second main section of railway track adjacent the exit end of said first main section, a track circuit for said first main section including a first main trackrelay, a track circuit for said auxiliary section including an auxiliary track relay, a track circuit for said second main section including a second main track relay, a fourth relay controlled by said three track relays, a coding relay controlled by said fourth relay, and means controlled by said coding relay and by said fourth relay for supplying train controlling current to the rails of said first main section.

- 11. In combination, a first main section of railway track, one of the rails of which is divided to form an auxiliary section, a sec ond main section of railway track adjacent the exit endof said first main section, a track circuit for said first main section including a first main track relay,a track circuit for said auxiliary section including an auxiliary track relay, a track circuit for said second main section including a second. main track relay, a fourth relay controlled by said three track relays, a coding relay controlled by said fourth relay, and means controlled by said coding relay, said fourth relay and said second main track relay for supplying train controlling current to the rails of said first main section.

12. In combination, a first main section of railway track, one of the rails of which is divided to form an auxiliary section, a second main section of railway track adjacent the exit end of said first main section, a track circuit for said first main section including a first main track relay, a track circuit for said auxiliary track section including an auxiliary track relay, a track circuit for said second main section including a second main track relay, a fourth relay, a pick-up circuit for said fourth relay including a back contact of said first main track relay and a front contact of said auxiliary track relay, a stick circuit for said fourth relay including said back contact of said first main track relay and a front contact of said fourth relay, a slow releasing relay controlled by a front contact of said second main track relay,a sixth relay; a pickup circuit for said sixth relay including a front contact of said first main track relay, a front contact of said auxiliary track relay, anda back contact of said fourth relay; a first stick circuit for said sixth relay including a front contact of said second main track relay and a front contact of said sixth relay, a second stick circuit for said sixth relay including a back contact of said slow releasing relay and a front contact of said sixth relay, and means controlled by said fourth and sixth relays for supplying train controlling current to the rails of said first main section.

13. In combination, a first main section of railway track, one of the rails of which is divided to form an auxiliary section, a second main section of railway track adjacent the exit end of said first main section, a track circuit for said first main section including a first main track relay, a track circuit for said auxiliary track section including an auxiliary track relay, a track circuit for said second main section including a second main track relay, a fourth relay, a pick-up circuitfor said fourth relay including a back contact of said first main track relay and a front contact of said auxiliary track relay, a stick circuit for said fourth relay including said back contact of said first main track relay and a front contact of said fourth relay, a slow releasing relay controlled by a front contact of said second main track relay, a sixth relay; a pick-up circuit for said sixth relay including a front contact of said first main track relay, a front contact of said auxiliary track relay, and a back contact of said fourth relay; a first stick circuit for said sixth relay including a front contact of said' second main track relay and a front contact of said sixth relay, a second stick circuit for said sixth relay including a back contact of said slow releasing relay and a front con tact of said sixth relay, and means controlled by a front contact of said fourth relay and a front contact of said sixth relay for supplying train controlling current to the rails of said first main section.

14. In combination, a first main section of railway track, one of therails of which is divided to form an auxiliary section, a second main section of railway track adjacent the exit end of said first main section, a track circuit for said first main section ineluding a first main track relay, a track circuit for said auxiliary track section including an auxiliary track, relay, a track circuit for said second main section including a second main track relay, a fourth relay, a pickup circuit for said fourth relay including a back contact of said first main track relay and a front contact of said auxiliary track relay, a stick circuit for said fourth relay including said back contact of said first main track relay and a front contact of said fourth relay, a slow releasing relay controlled by a front contact of said second main track relay, a sixth relay; a pick-up circuit for said sixth relay including a front contact of said first main track relay, a front contact of said auxiliary track relay, and a back contact of said fourth relay; a first stick circuit for said sixth relay includ ing a front contact of said second main track relay and a front contact of said sixth relay, a second stick circuit for said sixth relay including a back contact of said slow releasing relayand a front contact of said sixth relay, and means controlled by said fourth, said sixth and said second main track relays for supplying train controlling current to the rails of said first main section.

15. In combination, a first main section of railway track, one of the rails of which is divided to form an auxiliary section, a second main section of railway track adjacent the exit end of said first main section, a track circuit for said first main section including a transformer having its secondary connected across the rails at one end of the section and a first main track relay connected with the rails at the other end of the section, a track circuit for said auxiliary track section including an auxiliary track relay, a track circuit for said second main section including a second main track relay, a fourth relay, a pickup circuit for said fourth relay including a back contact of said first main track relay and afront contact of said auxiliary track relay, a stick circuit forsaid fourth relay including said back contact of said first main track relay and a front contact of said fourth relay, a slow releasing relay controlled by a front contact of said second main track relay, a sixth relay; a pickup circuit for said sixth relay including a front contact of said first main track relay, a front contact of said auxiliary track relay, and a back contact of said fourth relay; a first stick circuit for said sixth relay including a front contact of said second main track relay and a front contact of said sixth relay, a second stick circuit for said sixth relay including a back contact of said slow releasing relay and a front contact of said sixth relay, a coding relay controlled by a front contact of said fourth relay and provided with a first contact which is periodically operated at one frequency when said coding relay is energized and a second contact said transformer including a front contact of said fourth relay, said second contact of said codlng relay, a back contact of said second main track relay, and a front contact of said,

sixth relay. i

16. In combination, a first main section of railway track, one of the rails of which is divided to form an auxiliary section, a second main section of railway track adjacent the exit end of said first main section, a track circuit for said first main section including a first main track relay, 2. track circuit for said auxiliary track section including an auxiliary track relay, a track circuit for said second main section including a second main track relay, a fourth relay, a slow releasing relay controlled by a front contact of said second main track relay, a pick-up circuit for said fourth relay including a back contact of said" first main track relay and a front contact of said auxiliary track relay, a first stick circuit for said fourth relayincluding aback contact of said first main track relay, a front contact of said second main track relay, and a front contact of said fourth relay; second stick circuit for said fourth relay including a back contact of said first main track relay, a back contact of said slow releasing relay, and a front contact of said fourth relay, and means controlled by said fourth relay for supplying train controlling current to the rails of said first main section.

17. In combination, a first main section of railway track, one of the rails of which is divided to form an auxiliary section, a second main section ofvrailway track adjacent the exit end of said first main section, a track circuit for said first main section including a transformer having its secondary connected across the rails at one end of the section and a first main track relay connected with the rails at the other end of the section, a track circuit for said auxiliary track section including an auxiliary track relay, a track circuit for said second main section including a second main track relay, a fourth relay, a slow releasing relay controlled by a front contact of said second main track relay, a pick-up circuit for said fourth relay including a back contact of said first main track relay and a front contact of said auxiliary track relay, a first stick circuit for saidfourth relayincluding a back contact of said first main track relay, a front contact of said sec-- nd main track relay, and a front contact of said fourth relay; a second sticK circuit for said fourth relay'including aback contact of said first main track relay, a back contact of said slow releasing relay, and a front contact of said fourth relay, a coding relay controlled by a front contact of said fourth relay and provided with a first contact which is periodically operated at one frequency when said coding relay is energized and with a second contact which is periodically operated at a different frequency when the relay is energized, a first circuit for the primary of said transformer including a source of current and a back contact of said fourth relay;

a second circuit for the primary of said transformer including a source of current, a front contact of said fourth relay, said first contact of said coding relay, and a front Contact of said second main track relay; and a third circuit for the primary of said transformer including a front contact of said fourth relay, said second contact of said coding relay, and a back contact of said second main track relay.

18. In combination, a first main section of railway track, one of the rails of which is divided to form an auxiliary section, a track circuit for said main section including a main track relay, a track circuit for said auxiliary section including an auxiliary track relay, and means controlled by said two track relays for supplying train controlling current to the rails of said main section.

19. In combination, a first main section of railway track, one of the rails of which is divided to form an auxiliary section, and means effective upon the entrance of a train into said main section for at times supplying the rails of said main section with train con trolling current provided said auxiliary section is unoccupied. V

In testimony whereof I affix my signature.

BERNARD E. OI-IAGAN. 

